The present invention relates to a pulse photometry probe for measuring a pulse wave and a light absorption material in blood by the pulse photometry method.
In a related-art probe of this type, a light emitter and a light receiver are disposed in a long attaching member and a sensor holding member so as to be opposed to each other in a state where the probe is attached to a living body. In a use state, the sensor holding member is attached to a living body such as a finger while the sensor holding member is bent and then wound around the living body (see FIGS. 1 and 2 of JP-A-2004-49579 and FIG. 4 of JP-A-2003-225215).
In such a probe, however, the sensor holding member, the attaching member, and the like must protect the light emitter and the light receiver, and therefore have a certain degree of rigidity. Consequently, the probe is difficult to be properly fitted to the living body, so that apertures between the probe and the living body such as shown in FIGS. 6A to 6C may be sometimes formed. When disturbance light enters through the apertures and is detected by the light receiver, a false measurement may be caused.
Furthermore, cords which are placed in the sensor holding member, the attaching member, and the like have a certain degree of rigidity. Similarly with the sensor holding member and the attaching member, the cords hinder the probe from being properly fitted to a living body. In a configuration where a cable extends in a direction which is substantially perpendicular to a narrow-width edge of the probe and two lead wires in the cable are separated in a basal portion to be connected respectively to the light emitter and the light receiver, for example, the lead wires are disposed so as to extend to elements which are remote from the basal portion, without being substantially bent. In the case where the sensor is attached to a living body such as a finger, therefore, deformation in which the probe is formed into a shape fitted to the living body is hindered.